一种PID自调整系统的设计法

A Design Method of PID Anto-tuning System

针对工业控制中大量应用的PID控制,本文提出了一种用微型计算机完成对过程进行PID自调整控制的设计法。本法首先用递推最小二乘法对过程进行辨识,在求出实际过程的离散参数之后,按照模型匹配的方法,求出离散PID控制器的具体算法,从而自动完成系统的控制。本法的优点是简单,所需内存少。用浮点运算,整个程序只占4k字节(八位计算机)。系统的响应特性也比较满意。

PID control is the main control method widely used in industry.This paper discusses a method of designing PID auto-tuning control for processing control with a microcomputer.Firstly,the process model is identified with the recursive least squares method.Then with the matching method,a concrete algorithm of discrete PID controller is obtained and system control is accomplished automatically.Finally,two modeling examples are given to show the effectiveness of this method.The advantage of this method lies in its simplicity.It does not require a large number of memory units.It is based on floating operations,which need about 4K byte memory units(8bit microcomputer).Its process response characteristic is also better than that of other methods.